Automatic telephone switch



March 24, 1925.

. 1,531,134 c. D. RICHARD AUTOMATI C TELEPHONE SWI TCH 2 Sheets-Sheet lMarch 24, 1925.

' c. D. RICHARD AUTOMATIQ TELEPHONE SWITCH 2 Sheets-Sheet 2 PatentedMar. 24, 1925.

UNITED STATES v I 1,531,134 PATENT OFFICE.

CHARLES D. RICHARD, OF NEW BRIGHTON, NEW YORK, ASSIGNOR TO WESTERN ELEC-TRIO COMPANY, INCORPORATED, OF NEW YORK, N. Y., A 'CoRPoRATION OF NEWYORK.

AUTOMATIC TELEPHONE SWITCH.

Application filed June 15, 1921.

To all whom it may concern:

Be it known that I, CHARLES D. RICHARD, a citizen of France, residing atNew Brighton, in the county of Richmond, State of New York, haveinvented certain new and useful Improvements in Automatic TelephoneSwitches, of which the following is a full, clear, concise, and exactdescription.

This invention relates to automatic telephone exchange switchingapparatus, and more particularly to so-called selector and connectorswitches, the function of which is to extend connections betweensubscribers lines. The invention is especially directed to a multiplebrush selector or connector. that is, one in which an individual set ofcontact brushes is provided for each group of bank terminals, asdistinguished from that type in which a single set of brushes isemployed, as in the well-known Strowger switch.

The object in view is the provision of a simple and mechanical multiplebrush selector or connector, and in accordance with this object, theprincipal feature of the invention consists in a novel arrangementwhereby a single step-bystep driving motor is rendered operative toeffect both brush selection and terminal selection.

The switch comprises a terminal bank consisting usually of ten rowsoffixed contact terminals and an individual set of contact brushes foreach of said rows of terminals. The brushes are normally held out ofengageable relation to their respective rows of terminals and areadapted to be moved individually into engageable relation therewith.

When a calling subscriber operates his impulse sender, the first seriesof impulses corresponding with the first digit of the called subscribersnumber will operate the driving magnet to select a brush at the firstselector corresponding with the first digit.

The particular brush thus selected is then automatically moved out ofits normal position into engageable relation with its respective row ofbank terminals. It is then driven automatically step-by-step by the samedriving magnet as before mentioned to hunt for the terminals of an idletrunk. The second and third selectors, etc. operate in exactly the sameway as the first selectors.

Connector switches differ fundamentally from selectors only in thatterminal selecter line of the shaft of Fig. 1.

Serial No. 477,678.

Two specific embodiments of the invention are illustrated in thedrawings and described hereinafter: Both embodiments are directedspecifically to connector switches, the self-interrupting contactshaving been omitted, but it will be understood that the inventionapplies equally as well to selector switches.

lVith reference to the drawings, Figures 1, 2, 8 and 4 show thepreferred form, and Figures 5 and 6 show a modified form of theinvention.

Fig. 1 is an end view of the preferred form of switch from which aportion has been broken away to more clearly illustrate certain parts.Fig. 2 is a front elevation of the switch shown in. 1. Fig. 3 is anarbitrary cross sectional. view along. the cen- Fig. 4: is a detail of abrush carrier with a set of contact brushes mounted thereon. Fig. 5 is afragmentary elevation partly in cross section of the modified form ofthe invention and Fig. 6 is a cross sectional view along the -line 6-6of Fig. 5.

described first.

Reference character 1 designates a cast frame to which the various partsof the switch are attached and by which the switch may be mounted on asuitable rack.

The terminal bank 2 comprises ten arcuate rowsof fixed contact terminals3 superimposed and insulated from each other. Each row of bankterminalscomprises ten sets, each of which in turn comprises in the presentinstance two terminals. Each set of terminals and the terminals of eachset are insulated from each other. A layer of insulation 4 is placedbetween each succeeding row of terminals and an insulator separates theupper and lower terminals of each row. Since'there are ten rows ofterminals, each comprising ten sets there are in all one hundred sets ofterminals in the bank. Each setof'bank terminals is connected with atrunk or a subscribers line as the case may be, depending upon whetherthe switch is used as a selector or as a connector. If the switch isused as a selector, the bank terminals are connected to trunks leadingto other switches and if used as a connector they are connected directlyto subscribers lines. The bank is attached to the frame 1 by means ofbolts 6.

The shaft 7 is journaled at its ends in frame 1. A. sleeve 8 issecurelyattached to the shaft 7 near one end thereof by means of pin 9,and to this sleeve there is securely attached a circular disc 10 ofinsulating material. There is also securely attached to shaft-.17 ametal disc 11, which is integral with ratchet 12 and clutch 13.The'discs 10 and 11 taken together are referred to hereinafter as acarriage.

There are ten brush carriers such as that illustrated in Fig.4, eachconsisting of two rods 14 and 15, a lug 16, and insulators 17 and 18.Each of thecontact brushes 19 and 20 is secured to one of the rods,brush 19 being secured to rod and brush to rod 14:. The rods formconductors in circuit with the brushes. Attached to the upper side ofdisclO is a pair of arcuate brass strips 21 and 22 having aperturesthrough which rods lt and 15 extend. The brass strips are providedmerely as bearings for the rods and have no other function.

The brushes 19 and 20 are situated at difilerentrelative positions alongthe length of their respective rods, each pair of brushes beingpositioned to line up with one of the rows of bank terminals I In Fig. 3the brushes associated with the topmost row of bank terminals is shownand in this one case there is no insulator 17 provided, because thebrushes are situated so near the'end of the rods that the reinforcementprovided by insulator 17 is not needed. On all the other nine brushcarriers, insulator 17 is provided as shown in Fig.

Lugs 16 are rectangular in cross section and fit in correspondingrectangular apertures in plate 11 in which they slide freely.

Mounted near the top of the shaft and insulated therefrom, as well asfrom each other, are two conducting members 23 and each of which isprovided with ten spring fingers which bear on the upper ends ,of rodslt and 15 (see Fig. 3). Each conducting member is provided with anarcuate contact surface on one of which the stationbrush 25 bears and onthe other of which the stationary brush 2 6 bears.

The incoming line or trunk leading to the switch is connected to theterminals of brushes and 2G and as will be evident, an

electrical connection is established from the incoming line to all thecontact brushes 19 and 20 through the medium of brushes 25 and 26,conducting members 23 and 2 1 and rods let and 15.

Normally the brush carriers rest with their insulators is resting ondisc 11 and are held in that position by the tension of spring fingers23 and 2%. lVhen a brush carrier is in its normal position, the brushes19 and 20 thereon aredisposed on a line between adjacent rows of bankterminals as shown in Fig. 2, that is to. say the brushes are normallyout of the-path of their re spective rows of bankterminals.

Toselect a set of terminals a given row, the brush carrier correspondingto that row, must be lifted until its brushes are in alignment with thebank terminals as shown in Fig. 3, and then the shaft together with thecarriage and brush carriers is rotated until the selected brushes are inengagement with the desired set of bank terminals. It will be noted thatall the brush carriers. and brushes thereon are rotated simultaneously,but as only one brush carrier can be lifted out of its normal positionat a time, only i the brushes on that carrier can engage bank terminals.y

The member 27 is slidably mounted on shaft 7. It is provided with clutchteeth 27' which are adapted to engage the teeth of clutch 13 when thememberis lifted out of its normal position as shown in Fig. 2. An arm 272 is provided on member 27 to which is secured a pin 28, the object ofwhich will be presently shown. Member 27 is prevented from rotatingvwhile in its normal position, by reason of its engagement with thestepped bearing 29. i

Electromagnet 30 is the driving magnet and is ln'ovided with an armature31 to the end of which is pivotally secured a stepping pawl 32, whichupon energization of magnet 30 engages ratchet 12 and rotates ittogether with shaft 7 and the carriage. The .armature 31 pulls up inresponse to each current impulse transmitted to magnet 30 from thecalling subscribers dial and'moves all the brushes 19 and 20 around, adistance corresponding with the spacing of the bank 1 terminals.

, The end of armature 33 of electromagnet 34 is normally held inengagement with ratchet 12 by spring 35 and acts as a holding pawl toprevent restoration of the switch until such time as it should properlybe restored to normal.

Electromagnet 36 is provided with an armature 37 which carriesa'tail-piece 38 the end of which engages the member 27. It will beobvious that upon energization of electromagnet36 its armature 37 ispulled up and the tailpiece 3S lifts the member 27 out of its normalposit-ion as shown in Fig. 2 into the position shown in Fig. 3 whereuponthe teeth 2'? of member 27 engage the teeth of clutch 13.

Pin 28 moves upwardly with member 27 and engages lug 16 of any brushcarrier which happens to be in alignment therewith, and lifts the brushcarrier to a. position wherein the brushes 19 and 20 thereon are inalignment with their bank terminals.

Referring to Figs. 1 and 2, it will be noted that when the switch is inits normal non-operated position all the brushes 19 and 20 are disposedin an arc of the bank circle which is angularly separated from thebankterminals.

The pin 28 is so positioned that upon the completion of one rotary stepof the shaft 7 the first brush carrier. will be in alignment therewithand upon. the completion of two rotary steps, the second brush carrierwill be in alignment therewith, and so on for ten steps, when the lastbrush carrier would line up with pin 28. I

To select a set of terminals in a given row of the bank, the brushcarrier associated therewith is first selected and this operationconsists as will be apparent in rotating the carriage through a numberof steps corresponding with the particular brush carrier desired. If forinstance it is desired to connect with a set of terminals in the thirdrow from the top of the bank, the third set of brushes 19 and 20 fromthe left in Fig. 1 would be selected as that is the particular setassociated with the third row of bank terminals. 'Toselect the third setof brushes, three current impulses are transmitted to eleetromagnet andthe carriage together with the brush carriers are rotated three steps inresponse thereto.

.The third brush carrier isthen in aligmnent with pin 28. Immediatelyfollowing the cessation of the first series of impulses, that is thethree impulses just mentioned, electromagnet 36 is energized and inresponse thereto, member 27 together with pin 28 is lifted as heretoforedescribed. The third brush carrier is thereby lifted out of its normalposition into a position wherein its brushes 19 and 20 are in the pathof the third row of bank terminals.

Magnet 36 is maintained energized for a while, at least until the secondseries of impulses have started. The teeth 27 of member 27 engage theteeth of clutch 13 and upon further rotation of the carriage, member 27rotates with it. Pin 28 is thereby kept in engagement with lug 16 andcontinues to hold the selected brush carrier in its upward position.

After the operations above described, the second series of currentimpulses is transmitted to electromagnet 30 and the carriage isthereupon rotated a number of steps cor:

responding with the number of impulses comprising the second series, andthe selected brushes are brought into engagement with the desired set ofbank terminals.

The spiral spring 39 is provided for restoring the switch to normal. Theinner end of spring 39 is attached to shaft 7 and the outer end to ascrew engaging frame 1. To restore the switch to normal. electromagnet34 is energized and pulls its armature 33 out of engagement with theteeth of ratchet 12 whereupon the spring 39 rotates shaft 7 and thecarriage in the opposite direction to that in which it was previouslyrotated. Upon being restored to its normal angular position, member 27will drop into the position shown in Fig. 2 and the previously selectedbrush carrier will be restored by spring fingers 23 and 24.

The modified form of the invention shown in Figs. and 6 will now bedescribed.

The terminal bank is the same as previously described, and there are apair of contact brushes provided for each row of bank terminals.

All parts of the switch not shown are substantially the same as shownand described in connection with Figs. 1 and 2. Shaft 41 is rotatably journaled at its lower end in a bearing in the frame of the switch (notshown), and at its upper end it is journaled in the member 43. Thelatter member is in turn journaled in frame 1 as clearly shown in Fig.5.

A stepping ratchet 44, integral with a toothed clutch is securelyattached to shaft 41. A stepping magnet with armature and pawl such as30. 31 and 32 of Fig. 1 would be provided for operating ratchet 44.

The shaft 41 is provided with a key way 46 by means of which ten cams 42are securely attached thereto. Each cam 42 has a riser 42' and these areequally spaced around the shaft. as shown in Fig. 6.

The member 43, it will be noted, is U shaped and has a long narrow strip43 extending parallel to the shaft 41. This long narrow strip acts as asupport for the springs 47 and 48, the conducting strips 47 and 48, theinsulating strip therebetween and other parts forming the pile-up. Thesprings 47 and 48 are in pairs, one of each constituting a pair andthere are ten pairs.

The springs 47 are integral with conducting strip 47' and also with thearcuate contact strip 47 Springs 48 are integral with conducting strip48 and the arcuate contact strip 48 A pair of stationary contact springs49 engage the arcuate contact strip 47 and another pair of contactsprings (not shown) similar to springs 49 engage the contact strip 48The ten sets of contact brushes consis each of brushes 50 and 51., Eachpair of brushes 50 and 51 is securely attached to a lever arm 52 0finsulating material and they are all mounted on a long pin 53 aboutwhich they are rotatable. v The spring 47 and 48 engage the brushes 50and 51 respectively and normally hold the latter in their back positionsas shown in Fig. 6.

' Pin 53 passes through member 43 to which it is secured and projectsdownwardly therefrom and through an aperture in clutch member 54. Theclutch member is normally prevented from rotating by reason of itsengagement with the stepped bearing as J shown in Fig. 5. [Member 43 andthe parts carried thereby are accordingly normally prevented fromrotating about shaft 41.

The riser 42 on each cam 42 is adapted to engage one of the lever arms52 and actuate the latter so as to rotate the brushes 50 and 51 aboutthe pin 53 into the path of the terminal bank contacts.

To select abrush set, shaft 41, together with cams 42, is first rotatedone or more steps so that the riser 42 associated with the desired brushset is brought into engagement with the lever arm 52 thereof. In Fig. 6,shaft 41 and cams 42 are assumed to be "rotating in the directionindicated by the arrow and the riser 42 of the top cam is about tooperate the lever arm 52 and thereby move brushes 50 and 51 associatedtherewithinto the path of its associated row of bank terminals. Theclutch member 54 is then lifted and brought into engagement with clutchteeth 45 and out of engagement with the stepped portion of bearing 55.Then upon further operation of the stepping magnet the member 43 and allthe parts carried thereon together with clutch member 54 are rotatedtogether until the selected brush set is brought into engagement withthe desired set of bank terminals.

Electrical connection with the brushes 50 and 51 is effected through thecontact springs 49, arcuate contact strips 4'" and 48 conducting strips47 and 48 and springs 47 and 48.

Restoration is accomplished in substantially the same manner asdescribed in connection. with the switch shown in Figures 1, 3, 3 and 4.e

What is claimed is:'

1. In an automatic switch, a terminal bank comprising aplurality ofparallel rows of fixed contacts, a plurality of contact brush sets, onefor each row of fixed contacts,- said brush sets normally out ofalignment with their respective rows of fixed contacts, stepby-stepmeans operable to select said brush sets individually, andelectromagnetic means for moving the selected brush sets into align ment with their associated rowsof fixed contacts, said step-by-step meansoperable after the operation of said electromagnetiemeans to move theselected brush set into engagement with a fixed contact in itsassociated row. i

2. In an automatic switch, a terminal bank comprising a plurality ofsuperposed parallel arcuate rows of fixed contacts, a rotatable shaftconcentric with said arcu'ate rows, a carriage mounted on and rotatablewith said shaft, a plurality of longitudinally movable brush carriersmounted on said carriage, a brush set on each of said carriers, each ofsaid brush sets associated with one of said arcuate rows, but normallyout of alignment therewith, a member operable to move said brushcarriers longitudinally and to thereby put the brush sets thereon inalignment with their associatedarcuate rows, means for rotating saidshaft to selectively align said brush carriers individually with saidmember, means for operating said member, and means for selectivelydriving the selected brush set into engagement with a desired fixedcontact in its associated row.

3. In an automatic switch, a terminal bank comprising a plurality ofrows of fixed contacts, a rotatable carriage, a plurality of contactbrush sets on said carriage, each of said brush sets being associatedwith one of said rows of fixed contacts and normally out of alignmenttherewith, a clutch member rotatable with said carriagefa second clutchmember normally disengaged from said first clutch member, means formoving said second clutch member into engagement with said first clutchmember, means carried by said second clutch member operable when saidsecond clutch member is moved into engagement with said first clutchmemher to move any of said brush sets individually into alignment withtheir respectively associated rows of fixed contacts, and means forrotating said carriage.

4. An automatic switch comprising a plurality of parallel rows of fixedcontacts, a plurality of contact brush sets associated therewith andnormally movable in a path away from said contacts, a longitudinallymovable bar for each of said brushes, a

movable carriage for said bars, anoperating member common to said bars,means for operating said carriage to selectively move one of said barsin juxtaposition with said member, and means for operating said memberto move said selected brushes into the path defined by their'associatedcontacts.

5. In an automatic switch, a terminal bank comprising a plurality ofrows of fixed contacts, a rotatable carriage, a plurality of operablebars arranged on said carriage, a brush set arranged on each of saidbars, and a mechanism for imparting a three stage selecting movement tosaid brushes for en-' gaging said contacts selectively.

6. In an automatic switch, a terminal bank comprising a plurality ofrows of contacts,

a brush associated with each of said rows but normally out of engagementtherewith, a bar for each of said brushes, means for moving said barscollectively in a plurality of selective movements with reference tosaid contacts, and means for operating one of said bars after one ofsaid movements to move said brushes in contacting relation with saidfixed contacts.

7. In an automatic switch, rows of contacts, brushes associated withsaid rows but normally movable in a path away from said contacts, asequentially revolving member for selectively positioning said brusheswith reference to said contacts, and means for moving the selected brushwhen said memher is at rest into the path defined by its associatedcontacts, whereby another movement of said member is effective tointerengage one of said brushes with said contacts selectively. y

In witness whereof I hereunto subscribe my name this 13th day of June A.D. 1921.

CHARLES D. RICHARD.

